official NVidia repo install source from RPM, closed driver. All works out the box. Didn’t touch anything at all. Just updated kernel and it works. Got to know there are any issues only here in topic.
I have legacy GPU without GSP, so it doesn’t support open driver at all, only proprietary.
As an option try this repo for kernel: https://cdn.opensuse.org/repositories/Kernel:/stable/standard/ . I use this one, OpenSUSE is slow rolling out kernels and often end up with bugs, so I ignore shipped with distro kernels. And it worked as a charm, didn’t know issue exists at all. And not willing to try distro default one.
And just checked, official OpenSUSE Tumbleweed repo doesn’t ship 6.15 at all yet. So my question remains the same: how did you manage to fail? Where is kernel from and how it manages to fail?